JEE Mains · Physics · STD 11 - 14. waves and sound
An observer moves towards a stationary source of sound with a velocity equal to one-fifth of the velocity of sound. The percentage change in the frequency will be \(\dots \;\)%
- A \(20\)
- B \(10\)
- C \(5\)
- D \(0\)
Answer & Solution
Correct Answer
(A) \(20\)
Step-by-step Solution
Detailed explanation
\(f_{0}=\left(\frac{v+v_{0}}{v}\right) f_{s}\) \(f_{0}=\left(\frac{v+\frac{v}{5}}{v}\right) f_{s}\) \(f_{0}=\frac{6}{5} f_{s}\) \(\%\) change \(=\frac{f_{0}-f_{s}}{f_{s}} \times 100\) \(=\frac{1}{5} \times 100=20 \%\)
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